This is how it is done.
My work in my Mother's garden has unfortunately had a destructive effect on some of the spider's webs (Well, they will insist on anchoring their webs to weeds.)
This one was well into building a new one and showing how it is done.
I also watched another who was carefully cutting out a leaf that had fallen into her web.
This is a female common garden spider, or diadem spider (Araneus diadematus)